DAYTONA BEACH, Fla. — Sixteen Sprint Cup teams were forced to make changes to the roof flaps on their cars before the first practice Thursday afternoon at Daytona International Speed­way and all face possible sanctions next week, NASCAR announced.

The flaps are supposed to lay flat on the roof and hood. They deploy during an accident to keep a car from becoming airborne.

If the roof flaps don’t lay perfectly flat, it would allow air to be sucked into the cockpit. Teams have long attempted to find ways to draw air into the cockpit by not sealing rear windows, trunk decks or the rubber boots for the shifter.

One former team manager said teams have been grinding down the spacers with an emphasis on saving weight. Another longstanding challenge is to get as much weight as possible to the bottom of the car to make it more stable in the high banking.

According to NASCAR, the spacers are part of a special kit provided by manufacturers. The spacers “weren’t in compliance with the kits that were provided by the manufacturers,” NASCAR spokesman Kerry Tharp said.

Each team was forced to change the spacers before practicing.

SPECIAL SCHEMES: Several race teams will celebrate Independence Day weekend with special paint schemes.

Kevin Harvick’s car will be red, white and blue to promote Budweiser’s patriotic packing. The company said it will donate up to $1.5 million to the Folds of Honor program during the promotion.

Danica Patrick’s car will have its traditional bright green look, but it also will have a red, white and blue rear deck to showcase Go Daddy’s new .us domain.

McMurray’s car will feature stars and stripes; Almirola’s car will carry the colors of the U.S. Air Force; Dale Earnhardt Jr.’s car will promote the U.S. National Guard, Ryan Newman and Oral-B will pledge $100,000 to Hope for Warriors and J.J. Yeley’s scheme was designed by a quadriplegic soldier using a laser in his mouth.

On Saturday, the speedway will honor four Congressional Medal of Honor recipients before the race.

ON TRACK: Today’s schedule includes pole qualifying for the Subway Firecracker 250 is at 2:05 p.m., pole qualifying for the Coke Zero 400 at 4:05 p.m. and the 250-mile Nationwide Series race at 7:30 p.m.